German translation updates for Git 2.50

[ralfth]

Hi team,

please review German translation updates for Git 2.50. There are about 50 new or updated messages.
Update window closes on 12 June.

Thank you!

[github-actions]

Errors and warnings found by git-po-helper in workflow #54:

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INFO [po/de.po@73f9566]	5819 translated messages. 
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INFO [po/de.po@79201f4]	5768 translated messages, 41 fuzzy translations, 10 untranslated messages. 
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ERROR commit 79201f4: subject ("prepapre ...") does not have prefix "l10n:" 
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ERROR commit 79201f4: empty body of the commit message, no s-o-b signature 
INFO checking commits: 1 passed, 1 failed.        
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INFO downloading pot file from https://github.com/git-l10n/pot-changes/raw/pot/master/po/git.pot 

ERROR: fail to execute "git-po-helper check-commits"